Photographic products, processes and compositions



Oct. 17, 1967 J, F, DOWNEY 3,347,673

PHOTOGRAPHIC PRODUCTS, PROCESSES AND COMPOSITIOS Filed DSC. 19. 1963 my@y v `ATTOIRNEYS United States Patent O Filed Dec. 19, 1963, Ser. No.331,817 8 Claims. (Cl. 96-29) This invention relates to photography andmore particularly to products, compositions and processes for thedevelopment of photosensitive silver halide elements.

It is one object of the present invention to provide novel processes andcompositions for the development of silver halide emulsions, in whichnovel colored developing agents are used.

Another object is to provide novel processes and compositions for thedevelopment of silver halide emulsions, in which the novel developmentagent is capable of developing an exposed silver halide emulsion andimparting a reversed or positive colored image of the developed image toa superposed image-receiving material.

A further object is to provide novel silver halide developing agents andnovel products, processes and compositions suitable for use in preparingmonochromatic and multichromatic photographic images.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the process involving the severalsteps and the relation and order of one or more of such steps withrespect to each of the others, and the products and compositionspossessing the features, properties and the relation of elements whichare exemplified in the following detailed disclosure, and the scope ofthe application of which will be indicated in the claims.

The objects of this invention may be accomplished by the use of certainnovel dyes which have the ability to develop images present in theexposed silver halide emulsion; thus they may be referred to as dyedevelopers. These novel dyes or dye developers will be further describedhereinafter.

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawing wherein:

FIGURE 1 is a graphic illustration comparing the spectrophotometriccurves of the magenta dye developers of this invention -with a priorclass of magenta dye developers.

The photographic processes and compositions disclosed herein areparticularly useful in the treatment of an eX- posed silver halideemulsion, whereby a positive dye image may be imparted to anotherelement, herein referred to as an image-carrying or image-receivingelement.

U.S. Patent No. 2,983,606, issued May 9, 1961 to Howard G. Rogers,discloses diffusion transfer processes wherein a photographic negativematerial, such as photographic element comprising an exposed silverhalide emulsion, is developed in the presence of a dye developer toimpart to an image-receiving layer a reversed or positive dye image ofthe developed image by permeating into said emulsion a suitable liquidprocessing composition and bringing said emulsion into superposedrelationship with an appropriate image-receiving layer. The inventiveconcepts herein set forth provide novel dye developers for use in suchprocesses.

In carrying out the process of this invention, a photosensitive elementcontaining a silver halide emulsion is exposed and wetted with a liquidprocessing composition, for example by immersing, coating, spraying,flowing, etc., in the dark, and the photosensitive element superposedprior to, during or after wetting, on an image-receiving element. In apreferred embodiment, the photosensitive element contains a layer of dyedeveloper, and the liquid processing composition is applied to thephotosensitive element in a uniform layer as the photosensitive elementis brought into superposed position with an image-receiving element. Theliquid processing composition permeates the emulsion to provide asolution of dye developer substantially uniformly distributed therein.As the exposed silver halide emulsion is developed, the oxidationproduct of the dye developer is immobilized or precipitated in situ withthe developed silver, thereby providing an imagewise distribution ofunoxidized dye developer dissolved in the liquid processing composition.This immobilization is apparently due, at least in part, to a change inthe solubility characteristics of the dye developer upon oxidation, andespecially as regards its solubility in alkaline solutions. It may alsobe due, in part, to a tanning effect on the emulsion by the oxidizeddeveloping agent. At least part of this imagewise distribution ofunoxidized dye developer is transferred, by imbibition, to a superposedimagereceiving layer. The image-receiving layer receives a depthwisediffusion, from the emulsion, of unoxidized dye developer, withoutappreciably disturbing the imagewise distribution thereof, to provide areversed or positive, colored image of the developed or negative image.The image-receiving element may contain agents adapted to mordant orotherwise tix the diffused, unoxidized dye developer. I mbibitionperiods of approximately one minute have been found to give goodresults, but this contact period may be adjusted where necessary tocompensate for variations in temperature or other conditions. Thedesired positive image is revealed by stripping the image-receivinglayer from the silver halide emulsion at the end of the imbibitionperiod.

The dye developers ofthis invention may be utilized in thephotosensitive element, for example in, on or behind the silver halideemulsion, or they may be utilized in the image-receiving element or inthe liquid processing composition. In a preferred embodiment, a coatingor layer of the dye developer is placed behind the silver halideemulsion, i.e., on the side of the emulsion adapted to be located mostdistant from the photographed subject when the emulsion is exposed andpreferably also adapted to be most distant from the image-receivinglayer when in superposed relationship therewith. Placing the dyedeveloper behind the emulsion layer, as in the preferred ernbodiment,has the advantage of providing increased contrast in the positive image,and also minimizes any lightfiltering action by the colored dyedeveloper. In this preferred embodiment, the layer of dye developer maybe applied by using a coating solution containing about 0.5 to 8%, byweight, of the dye developer. Similar concentrations may be used if the`dye developer is utilized as -a component of the liquid processingcomposition. In an especially useful mode of disposing the dyedevelopers in the photosensitive elements, the dye developer isdissolved in a water-immiscible solvent and then dispersed in a gelatincoating solution.

The liquid processing composition which is used in the processes hereindisclosed comprises at least an aqueous solution of an alkalinecompound, for example, diethylamine, sodium hydroxide or sodiumcarbonate, and may contain the dye developer. In some instances, it maycontain an additional silver halide developing agent. If the liquidprocessing composition is to be applied to the emulsion by being spreadthereon, preferably in a relatively thin, uniform layer, it may alsoinclude a viscosity-increasing compound constituting film-formingmaterial of the type which, when spread over a water-absorbent base,will form a relatively rm and relatively stable film. A preferredfilm-forming material is a high molecular weight polymer such as apolymeric, water-soluble ether inert to n .j t an alkali solution, as,for example, a hydroxyethyl cellulose or sodium carboxymethyl cellulose.Other iilm-forming materials or thickening agents whose ability to increase viscosity is substantially unalected when left in l solution fora long period `of time may also be used.

The novel dye developers of this invention are anthraquinone dyes havingthe formula:

wherein each Z may be hydrogen, a hydroxy or an amino group; X is analkylene radical, preferably a lower alkylene radical containing from1-6 carbon atoms; and Y is s-dihydroxyphenyl silver halide developingradical, e.g., p-dihydroxyphenyl, o-dihydroxyphenyl, or halogen or alkylsubstituted derivatives thereof.

As illustrations of suitable alkylene radicals comprehended by X,mention may be made of radicals such as (l NH: (lH Marcin-O \u/ 1 1 H on1-amino-2-(2 ,5'-dhydroxyphenyl-methylamino) 4hydroxyanthraquinone o tNH, 0H

H l IH-enfriar@ ll o 0H on 1-amino-2-(a-methy1[3',4'-dihydroxypheny1d'ethylaminm 4-hydroxy-ant-hraquinone tte NH-(oHmon on Y t l-umino-Z- (zeta- [3',4-dihydroxyp-henyl]-hexylamino) -4- hydroxy-anthraquinone on o NH. t onll (IJHS l Nit-captif@ ll NH, o 0H on 1,5-diamino-2- (a-methyl-- [2,5'dihydroxypheny1] -ethylt amino) 4,8-dihydroxy-anthraqutnone OH ONH-CH-CHn- OH v on The dye developers of this invention may be preparedby condensing an anthraquinone of the formula:

(B) (n) NH2 l R s Z O OH wherein Z has the same meaning as above; R is asuitable halogen, prefer-ably bromine, `or a phenoxy group, e.g.,

etc.; with a compound of the formula;

wherein X has the same meaning as above and Y1 is a protecteddihydroxYPhenyl silver halide developing radical, e.g., an orthoorpara-bis-alkoxyphenyl, benzyloxyphenyl radical, etc.

Subsequent removal of the protective groups, e.g., by

hydrolysis, will provide the desired compound of Formula A.

2-chl0ro1,5-diamino-4, S-dihydroXy-anthraquinone t im Q Y O OHl-amino-l-hydroxy-2-phenoxy-anthraquinone l-amino2 p-chlorophenoxy)-4-11ydroxyfanthraquinone As examples of useful compounds within thescope of the Formula C mention made be made of:

O C H3 2-zeta-aminohexyl-1,4-di1nethoxybenzene The following nonlimitingexample illustrates the preparation of the novel dye developers of theinvention:

Example 1 methoxy-benzene and 2.1 gm. of potassium carbonate was heatedon a steam bath for 20 hours. The resulting mixture was cooled andpoured into 4 liters of 2.5% HC1 and ice. The precipitate was filteredand dried. The dry reddish solid was extracted with methanol leavingbehind the insoluble 1-amino2(amethyl-,8-[2,5dimethoxyphenyl]ethylamino) 4 hydroxy-anthraquinone, having thefollowing structural formula:

The following analysis was obtained: Calculated: C, 69.43; H, 5.59; O,18.50; N, 6.48. Found: C, 69.58; H, 5.58; O, 18.71; N, 6.42. A mixtureof 10 gm. of l-amino- Z-(-methyl -[2',5 dimethoxyphenyl] -ethylaminO)-4hydroxy-anthraquinone (prepared in the foregoing manner) .and gm. ofpyridine hydrochloride was heated at 225 C. for 9 minutes. The resultingsolution was then poured into 3 Iliters of water and ltered. Theresulting filter cake was crystallized from toluene-ethanol to givel-arnino 2(oc-methyl--[2,5-dihydroxyphenyl]-ethylamino)-4-hydroxy-anthraquinonewhich melted at 254- 261 C.; had a spectral absorption curve with max,at 528 and 566 mu in methyl Cellosolve; Ve528=21,000 and e567=20,500having the following structural formula:

NH2 (i) o H il l (IHS NH-oH-CH2- o on on Example 2 A photosensitiveelement was prepared by coating a gelatin subcoated film base `at aspeed of 10 feet/minute with -a solution comprising 0.32 g. of1-amino-2-(a methyl [2',5 dihydroxyphenyl] ethylamino)4hydroxy-anthraquinone [Formula 1] and 15 drops of dimethylformamidedissolved in 10 cc. Of 2% cellulose `acetate hydrogen phthalate inacetone. After this coating dried, a green-sensitive silver iodobromideemulsion was coated on at a speed of 5 feet/ minute and allowed to dry.This photosensitive element was exposed for 2 seconds and processed byspreading, between the thus exposed photosensitive element and asuperposed image-receiving element, an aqueous processing compositioncomprising:

Water, cc. 100.00 KOH, g. 11.20 Hydroxyethyl cellulose (high viscosity)[commercially available from Hercules Powder Co., under the trade nameof Natrosol 250], g. 3.90

Benzotriazole, g. 3.50 Sodium thiosulfate, g. 0.50 N-benzyl-a-picoliniumbromide, g. 2.00 Zinc nitrate, g. 0.50 Lithium nitrate, g. 0.50

paper support. After an imbibition period of approximately one minute,the image-receiving element was separated and contained Ia magentapositive image.

Exdmple 3 The procedure described in Example `2 was repeated, exceptthat the dye developer was dispersed in a layer of gelatin. The coatingsolution from which the dye developer was coated was prepared by adding0.46 g. of the dye developer dissolved in 1.0 cc. of cyclohexanone` and`1.0 cc. of N,Ndiethyllauramide. This mixture was agitated in a Waringblendor for one minutewith a solution of 5.0 g. of 10% gelatin solution,1.3 cc. of water, and 1.0 cc. of alkanol B. 6 cc. of the resulting dyedispersion was added to 7 cc. of water containing 2.0 cc. of 12% aqueoussaponin, and then coated on the gelatin subcoated film base at a speedof 10 feet/minute. Exposure and processing in the manner described inExample 2 yielded a magenta dye image.

The addition of 0.2 g. of 4-methylphenyl-hydroquinone to the processingsolution of ExamplesZ and 3 gave comparable images having appreciablylower Dmms,

Prior to the present invention, it had not been thought possible vtoprepare compounds within the scope of Formula A; In other words, it wasnot thought possible by one skilled in the art that reacting a compound`of Formula B with a compound of Formula C would produce an aminosubstituent placed ortho to the amino group on the1-amino-4-hydroxy-anthraquinone nucleus, since attempts to substitute anamino group in the 2-position of a l,4-diamino-anthraquinone have beenunsuccessful.

Where each Z of Formula A is hydrogen, the resulting compounds aremagenta dye developers possessing excellent stability and spectralabsorption characteristics. In photographic processes such as aredescribed and Claimed in the aforementioned U.S.`Patent No'. 2,983,606,particularly in such processes for preparing multicolor images, it isextremely desirable that the dye developers ernployed possess the.desired spectral absorption characteristics, as well as being stable tolight, heat and humidity, so as to provide a stable image of the desiredcolor. As is frequently the case, a magnete. dye of the proper color,e.g., having the proper blue transmission, may not possess the desiredstability. Conversely, magenta dyes hav- -ing good light stabilityfrequently arenot of the proper color, especially for use in multicolorprocesses.

The magenta dye developers of the present invention are of particularvalue in that they are both highly stable and exhibit excellent colorfor use in preparing color images, particularly multicolor images whereoptimum color reproduction is desired.

Thus, while the magenta dye developers of this invention are` neitherthe most stableheretofore known nor do they possess the most optimumspectral absorption characteristics, `they are unusual in that theycombine these properties to a high degree soas to provide magenta dyedevelopers extremely useful in the aforementioned photographic processesand products, particularly in such products and processes for preparingmulticolor images.

As shown in FIGURE 1, the spectrophotometric curve of a typical magentadye developer of this invention, specically1-amino-2(-methyl--[2,5-dihydroxyphenyl]-ethylamino)-4-hydroxy-anthraquinone (solid line) is cornpared with atypical 2-alkoxy-1,4-diamino-anthraquinone magenta dye developer of theprior art, specifically 1,4- diarnino` 2 (e [2',5'dihydroxy-hydrocinnamido] pentoxy)anthraquinone (dotted line), thesolvent in each case beingl methyl cellosolve. The last-named dyedeveloper an 'analogous Z-aIkOXy-anthraquinone dye developers aredescribed and claimed in copending application Serial No. 152,014, ledNovember 13, 1961 in the name of lohn F. Downey and Myron S. Simon.

While only a single species of each class of dye developers has beenshown for purposes of comparison, it will be understood that the variousspecies of the chromophoric systems illustrated. in the drawing havesubstantially identical curves.

It will be observed that the AML of the dye developers of this inventionare shifted more towards the violet or a lower wavelength in the visiblespectrum, and they have less absorption in the red region and moreabsorption in the green region of the spectrum than do the illustratedprior dye developers. More specifically, the illustrated dye developerof this invention (Solid line) has a spectral absorption curve with max.at 528 and 566 ma; e528=2l,000 and E56-1:20500; while the prior`2-alkoxy dye developer (dotted line) has a spectral absorptioncurvewith MWL at 534 and 572 mit; e534=l6,300; e572: 17,400.

The difference in spectralabsorption characteristics illustrated in thegraph permits the magenta dye developers of this invention to affordmore desirable color balance or accuracy of color reproduction inmulticolor images prepared in the manner heretofore described.

The dye developers of this invention are alsoI useful in integralmultilayer photosensitive elements for use in multicolor diffusiontransfer processes. As an example of such photosensitive elements,mention may be made of the photosensitive elements disclosed and claimedin` the copending U.S. application of Edwin H. Land and Howard G.Rogers, Serial No. 565,135, led February 13, 1956, wherein at least twoselectively sensitized photosensitive strata are superposed on a singlesupport and are processed, simultaneously and without separation, with asingle common image-receiving element. A suitable arrangement of thistype comprises a support carrying a red-sensitive silver halide emulsionstratum, a green-sensitive silver halide emulsion stratum and ablue-sensitive silver halide emulsion stratum, said emulsions havingassociated therewith, respectively, a cyan dye developer, a magenta dyedeveloper and a-yellow dye developer. In one of the preferredembodiments of photosensitive elements of this type, the dye developersare disposed in separate alkali-permeable layers behind thephotosensitive silver halide emulsionstraturn with which they areassociated.

The photosensitive elements within the scope of this invention may beused in film units which contain a plurality of photosensitive frames.The photosensitive elements of this invention are especially useful incompositev roll film `and film `pack structures intended for use inaPolaroid Land Camera, sold by Polaroid Corporation, Cambridge 39,Massachusetts, or a similar camera structure such, for example, as theroll filmv type camera forming the `subject matterof U,S. Patent No.2,435,717, issued to Edwin H. Land on February 10, 1948, or the filmpack type camera shown in U.S. Patent No. 2,991,702 issued to Vaito K.Eloranta on July 11, 1961. In general, such composite roll lms comprisea photosensitive roll, a roll of image-receiving material and aplurality of pods containing an aqueous alkaline processing solution.The rolls and pods arevso associated with each other that, upon lprocessing, the protosensitive element may be superposed on theimage-receiving element and the pods may be ruptured to spread'theaqueous alkaline processing solution between the superposed elements.The nature and construction of the pods used in such units are wellknown to the art. See, for example, U.S. Patents Nos. 2,543,181 and2,634,886, issued to Edwin H. Land.

It will be noted that the liquid processing composition may contain oneor more auxiliary or accelerating silver halide developing agents, suchas p-methylaminophenol (Metol); 2,4-diaminophenol (Amidol);benzylaminopheno1', hydroquinones; a substituted hydroquinone such astoluhydroquinone, phenylhydroquinone, or i 4methyl phenylhydroquinone;or a 3-pyrazolidone such as 1- phenyl-S-pyrazolidone. i These silverhalide developing agents are substantially colorless, at least in theirunoxidized form. It is possible that some of the dye developer oxidizedin exposed areas may be oxidized by an energy transfer` reaction withoxidized auxiliary developing agent.

In addition, development may be effected inthe pres- Q ence of an oniumcompound, particularly a quaternary ammonium compound, in accordancewith the processes disclosed and claimed in the copending application ofMilton Green and Howard G. Rogers, Serial No. 50,851, led August 22,1960, now Patent No. 3,173,786.

The dye developers of this invention may be used also inconventionalphotographic processes, such as tray or tank development ofconventional photosensitive films, plates or papers to obtainblack-and-white, monochromatic or toned prints or negatives. By way ofexample, a developer composition suitable for such use may cornprise anaqueous solution of approximately 1-2% of the dye developer, 1% sodiumhydroxide, 2% sodium sulfite and 0.05% potassium bromide. Afterdevelopment is completed, any unreacted dye developer is washed out ofthe photosensitive element, preferably with an alkaline washing mediumor other medium in which the unreacted dye developer is soluble. Theexpression toned is used to designate photographic images wherein thesilver is retained with the precipitated dye, whereas monochromatic lisintended to designate dye images free of sin It should be noted that thedye developers of this medium are self-sufficient to provide the desiredcolor image and do not depend upon coupling reactions to produce thedesired color. They thus provide a complete departure from conventionalphotographic color processes in which the color is produced by acoupling reaction between a color former or coupler and the oxidizeddeveloping agent, as well as so-called auto-coupling processes in whichcolor is obtained by a reaction of the oxidized developing agent withunoxidized developing agent.

It will be apparent that, by appropriate selection of theimage-receiving Ielernent from among suitable known opaque andtransparent materials, it is possible to obtain either a coloredpositive reflection print or a colored positive transparency. Likewise,the inventive concepts herein set forth are adaptable for multicolorwork by the use of special photographic materials, for example, filmmaterials of the type containing two or more photosensitized elementsassociated with an appropriate number of image-receiving elements andadapted to be treated with one or more liquid processing compositions,appropriate dye developers suitable to impart the desired subtractivecolors being incorporated in the photosensit'ized elements or in theliquid processing compositions. Examples of such photographic materialsare disclosed in U.S. Patent No. 2,647,049 to Edwin H. Land.

As examples of useful image-receiving materials, mention may be made ofnylon, e.g., N-methoxymethyl-polyhexamethylene adipamide, polyvinylalcohol, and gelatin, particularly polyvinyl alcohol or gelatincontaining a dye mordant such as poly-4-vinylpyridine. Theimage-receiving element also may contain a development restrainer, e.g.,l-phenyl-S-mercaptotetrazole, as disclosed in the copending applicationof Howard G. Rogers and Harriet W. Lutes, Serial No. 50,849, filedAugust 22, 1960, now Patent No. 3,265,498.

The dye developers herein set forth are also useful in the formation ofcolored images in accordance with the photographic products andprocesses described and claimed in U.S. Patent No. 2,968,554, issued toEdwin H. Land on January 17, 1961.

The novel compounds herein disclosed are also suitable for use as dyesfor textile fibres, such as nylon.

In the preceding portions of the specification, the expression color hasbeen frequently used. This expression is intended to include the use ofa plurality of colors to obtain black.

Since certain changes may be made in the above products, compositionsand processes without departing from the scope of the invention hereininvolved, it is intended that all matter contained in the abovedescription shall be interpreted as illustrative and not in a limitingsense.

l0 What is claimed is: K 1. A novel photographic developer compositioncornprising an yaqueous alkaline solution of a colorless silver halideauxiliary developing agent and an anthraquinone dye of the formula:

z o 0H wherein each Z is selected from the group consisting of hydrogen,hydroxy and amino groups; X is a lower alkylene radical; and Y is ahydroxyphenyl silver halide developing radical.

2. A novel photographic developer composition comprising an aqueousalkaline solution of l-amino-Z-(ocmethyl- [2',5 dihydroxyphenyl]ethylamino) 4-hydroxy-anthraquinone and a colorless silver halideauxiliary developing agent.

3. A novel photographic product comprising a support, a silver halideemulsion in a layer on said support, and a dye developer in a layer onthe same side of said support as said emulsion, said dye developercomprising an anthraquinone dye of the formula:

IY zooH wherein each Z is selected from the group consisting ofhydrogen, hydroxy and amino groups; X is an alkylene radical; and Y is adihydroxyphenyl silver halide developing radical.

4. A novel photographic product comprising a support, a silver halideemulsion in a layer on said support and 1 amino-2-(a-methyl-,B-[2',5dihydroxyphenyl]- ethylamino)-4-hydroxy-anthraquinone in a layer on thesame side of said support' of said emulsion.

5. In a process of forming a photographic image in color, the stepswhich comprise developing a latent image contained in an exposed silverhalide emulsion by contatcing said emulsion with an aqueous alkalinesolution conltaining an anthraquinone dye developer of the formu a:

wherein each Z is selected from the group consisting of hydrogen,hydroxy and amino groups; X is an alkylene radical; and Y is adihydroxyphenyl silver halide developing radical; oxidizing said dyedeveloper in developed areas to provide in said emulsion a predetermineddistribution of unoxidized dye developer and transferring at least partof said distribution of said unoxidized dye developer by imbibition fromsaid emulsion to an imagereceiving element in superposed relationshipwith said emulsion to impart to said image-receiving element a positivedye image of the developed image.

6. The process as defined in claim 5 wherein said cornpound isl-amino-Z-(a-methyl--[2,5dihydroxyphenyl]ethylamino)-4-hydroxy-anthraquinone.

7. A photographic process which comprises exposing a photosensitivesilver haldie emulsion and contacting said exposed silver halideemulsion With an aqueous alkaline solution containing au anthraquinonedye of the for.-

mula:

1 2 pound is 1-arnino2( a-methyl-[2',5 '-dihydroxyphenyl]- ethylamino)-4-hydroxy-anthraquinone.

References Cited UNITED STATES PATENTS 2,983,606 5/1961 Rogers 96-293,192,117 6/ 1965 Kaiser et al. 26o-380 OTHER REFERENCES Venkataraman,Synthetic Dyes, vol. 2,` page S86, Academic Press, N.Y. (1952).

I. TRAVIS BROWN, Primary Examiner.

15 NORMAN G. TORCHIN; Examiner.

5. IN A PROCESS OF FORMING A PHOTOGRAPHIC IMAGE IN COLOR, THE STEPSWHICH COMPRISE DEVELOPING A LATENT IMAGE CONTAINED IN AN EXPOSED SILVERHALIDE EMULSION BY CONTACTING SAID EMULSION WITH AN AQUEOUS ALKALINESOLUTION CONTAINING AN ANTHRAQUINONE DYE DEVELOPER OF THE FORMULA: